Prefabricated chimneyes and vents



Feb. 14, 1967 P. s. KELsr-:Y 3,303,618

PREFABRICATED CHIMNEYS AND VENTS Filed May 28, 1964 2 Sheets-Sheet l INVENTOR P904 H545 y ATTORNEYS Feb. 14, 1967 P.s. KELsEY PREFABRICATED CHIMNEYS AND VENTS 2 Sheets-Sheet 2 Filed- May 28, 1964 INVENTOR Bba flj'ffzsfr United States Patent C f 3,303,618 PREFABRICATED CHBVINEYS AND VENTS Paul S. Kelsey, 301 Paxon Hollow Road, Media, Pa. 19063 Filed May 28, 1964, Ser. No. 370,807 11 Claims. (Cl. 52-269) This invention relates to an improved all masonry prefabricated chimney or vent employing a novel joint to eliminate the need of total dimensional stability of all prefabricated components, and or to provide units, the inner lining of which can be easily jointed with one type of cement (acid and heat proof) While the outer portion is easily jointed with another type of cement (weather-proof mortar), without the danger of one getting mixed with and so contaminating the other as to render it unt for its particular function.

ln the following specification the principles of the present invention are applied to both chimneys and vents although it is recognized that these terms have achieved somewhat distinct meanings in the art. For instance, the Underwriter Laboratories have defined a vent as a line suitable only for the disposal of relatively low temperature products of combustion which emerge from gas fired home heating and hot water heating appliances approved by Underwriter Laboratories. The maximum temperature involved in a vent is about 400 F. A chimney is defined as a flue suitable for disposing the products of combustion of oil, coal or wood fueled appliances, the maximum temperature being as high as 1700 F. Therefore, the basic difference between vents and chimneys is the ability of their components to endure the temperatures involved and their ability to safely contain the temperatures involved.

It has been difficult to devise a satisfactory prefabricated all masonry chimney or vent at a reasonable cost. The first reason is that the commonly used heat resistant ceramic components cannot be economically made uniformly to the same size. Heretofore, in order to make a chimney `from a plurality of superimposed prefabricated blocks, each having a tubular refractory lining and a body of insulating material surrounding the lining, each block had to be substantially the same size or otherwise they would not fit together satisfactorily on the job site. The raw materials such as clay and shale used in making todays commonly used flue linings are always nonuniform and as a result the linings produced vary in size due to non-uniform shrinkage. Furthermore, even if uniform raw materials were available, consistently sized burned clay `or shale flue lining sections could not be economically manufactured, with the processing equipment available today. As a result straight, round, rectangular or square burned clay or shale flue lining sections with a high degree of size uniformity are not available. Thus, the length of the lining may vary, the widths may vary and rarely are the top and bottom or any two sides exactly parallel. As now practiced, the lack of parallelism of the sides is ignored and adjusted 'by using thick and thin mortar joints as required to lay up a series of linings that are reasonably plumb. Therefore, the cause of the dimensional instability of the ceramic components, a satisfactory prefabricated all masonry chimney or vent has not been commercially available.

The second major past barrier to the construction of satisfactory masonry chimneys and vents made up and of prefabricated units, has 'been the difficulty of correctly applying separate jointing materials to the inner acid and heat proof lining and the outer insulating and weather 'resistant casing. Any chimney or vents effectiveness vand usable life span is heavily dependent on maintain- 3,303,518 Patented F eb. 14, 1967 ing a continuous acid proof inner lining and a continuous weatherproof exterior casing. Normal brick and block mortar has very poor resistance to even the weak sulphuric acid. generated in most every chimney or vent. Air setting acid proof cement is a relatively expensive material compared to ordinary brick mortar. To use air setting acid-proof cement for both inside and outside joints would `be too costly, as it costs up to fifteen times as much per pound as does brick mortar,

Also chimney and vent linings are relatively thin, the area to be jointed with acid-proof cement only amounting to as little as one sixth and never more than half that area to be jointed with ordinary brick mortar. Also acid-proof cement is normally used in a very thin, wet, slurry like state, thereby permitting the attainment of very thin joints-thus keeping its use per joint to a minimum level. Brick mortar on the other hand is relatively stiff as used and as a result thin joints are hard to achieve. If there develops competition for space the more important acid-proof cement is pushed out on one side by the stiffer brick mortar. Should the acid-proof cement become contaminated with brick mortar, it no longer is capable of preventing acid penetration between sections of the interior lining and the exterior non-acid resistant insulating casing. Regardless of the dimensional component sta-bility that may someday be achieved by the use of new materials or new processes, this jointing problem will remain and must be solved before prefabricated masonry or masonry equivalent chimneys or vents can prove satisfactory.

Therefore, it is a major object of this invention to provide an economical and most satisfactory all masonry prefabricated chimney or vent made up of units having an inner non-dimensionally sta-ble refractory lining surrounded by a body of thermal insulating material that is dimensionally stable with or without an additional outer casing of dimensionally unstable burned clay.

The other principal object of this invention is to design units, which can easily lbe assembled one on top of the other, have their inner linings jointed with appropriate acid-proof cement and their outer casings jointed with suitable weather resistant mortar, each joint to be within its-own desirable thickness range and the possibility of contamination or misplacement of either jointing material being practically eliminated.

Another object of this invention is to provide an improved joint for prefabricated chimneys or vents having an inner refractory lining surrounded by a body of thermal insulating material.

Still another object 0f this invention is to provide an all masonry prefabricated chimney or vent that is highly resistant to weathering.

Another object of this invention is to provide an all masonry prefabricated chimney or vent in which the joints of adjacent refractory lining sections conveying the products of combustion are acid resistant.

Still another object of this invention is to provide an all masonry prefabricated chimney or vent that can be manufactured and installed at a cost below that of conventional masonry chimneys and vents.

Still another object of this invention is to provide an all masonry prefabricated chimney or vent in which there are no vertical joints.

A further object of this invention is to provide an improved joint for prefabricated chimney or vent blocks that imparts substantial strength to the finished chimney or vent.

Still further objects andthe entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, .are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

In the accompanying drawings forming a part of this specification,

FIGURE 1 is a generally schematic elevational view of a chimney constructed of prefabricated blocks illustrating the principles of the invention;

FIGURE 2 shows in section portions of two blocks according to the invention and especially illustrate the novel joint between the blocks;

FIGURE 3 is a top plan view of one of the blocks;

FIGURE 4 is a vertical section of one of the blocks of the prefabricated chimney illustrated in FIGURE l;

FIGURE 5 is a vertical section of a further embodiment of a block forming a part of the invention;

FIGURE 6 is a vertical section -of a block similar to that shown in FIGURE 4 but being provided with a laterally extending passageway; and

FIGURE 7 is a vertical section of the bottom block of the Prefabricated chimney illustrated in FIGURE l.

Referring more specifically to the drawings, FIGURE l illustrates a prefabricated chimney generally indicated at 10 erected in a building which passes through rfloors 12 and 14, ceiling 16 and roof I8. A gas heating furnace 2t) and .a gas hot water heater 22 located on the basement floor 24 are connected to the chimney by flue outlet conduits 26 and 28 respectively. The bottom block 30 of the chimney 10 serves as the base of a soot collection cavity and is provided with a cast ir-on cleanout door assembly 32. That portion of the chimney extending above the roof lis topped olf with a brick outer casing 34 laid around clay flue liners 35 to give the appearance of a conventional brick chimney.' To accomplish this, the individual prefabricated blocks indicated as 36 of the chimney 10 end where the exterior brick casing 34 begins or in other words Va standard brick chimney is laid on top of a prefabricated chimney or vent with or without the use of a transition block 37. The Vtransition block 37 is identical in construction to the prefabricated blocks 36 except that theY outer diameter is greater in order to achieve a transition in size from the narrower chimney or vent 10 to the broader brick outer casing 34. Y

FIGURE 4 discloses a single prefabricated block 36 used in constructing the chimney 10 and consists ofan inner refractory lining 38 having a central passageway 42 extending longitudinally therethrough with an outer body of thermal insulating material 40. The refractory Ilining 38 is preferably composed of burned clay or shale or of other economical refractory material that can be processed into the desired form and the body of thermal insulation 40 is preferably made from concrete or a similar cementious material which may optionally contain thermal insulating material such as asbestos ber.

According to the preferred form of the invention illustrated in FIGURE 4 the body of insulating material40 is molded or cast on the refractory lining 38 so as to circumferentially engage the exterior surface 44 Vof the refractory lining. As best shown in FIGURE 4 the body 40 and the lining 38 are arranged with respect to each other according to the invention so that the lining has a greater length than the body and the lining is axially displaced with respect to the body so that the lining extends upwardly frorn the body as indicated at 46. At the opposite end 48 of the block 36 a recess 50 is delined by the axial displacement of the lining 38 with respectV to the end 48 of the body 40 and the relieving of a generallyV annular portion of body materialV radially outwardly from the end 52 ofthe lining. As shown, the recess 50 is formed so that the lining 38 terminates within the recess Vand denes a square shoulder 54 with the body 40. The width of the recess 50 is greater than the width of 1A" as space for mortar.

of the refractory lining 38. The unrelieved portion of the end 48 extending radially outwardly from the recess 50 defines a second shoulder 56 extending to the outer surface 58 of the body 40. The depth of the recess 50 is less than the -axial extent of the extension 46 by an amount which provides for the receiving of mortar or similar cementious material between adjacent blocks of a similar character plus whatever is necessary to take care of the maximum plus and minus variations in length that could occur in the inner clay lining 38, as will be more fully discussed hereinbelow.

The minimum difference between the depth of the recess 50 and the length of the extension 46 is equal to the minimum mortar joint thickness desired between adjacent blocks. The mortar joint thickness is defined as the annular space between the upper end 60 of the body 40 of the lower block 36 and the shoulder 56 at the lower end of t-he body of the upper block 36 as shown in FIGURE 2. The minimum mortar joint thickness is preferably approximately one-quarter inch but may vary for example from one-quarter inch to seveneighths of an inch. The length of the extension 46 may vary for example from one inch to four inches, preferably being no less than two inches. The joint thickness will actually vary from the desired minimum to the minimum plus the total variation in the length of the refractory lining sections. As an example, suppose the refractory linings 38 have an average length of 12" but vary as much as plus or minus W16. Assuming that the minimum mortar joint thickness desired is 1A," then the length of the body of thermal insulating material 46 would be 12 less 5/16 less l or 11%6. Therefore, on assembly, the adjacent refractory linings would always engage with each other (less a very thin layer of acidproof cement) `and the adjacent bodiesl of insulating material 40 would always have a minimum separation This joint space could of course, reach a thickness of 74; when refractory lining 38 would have a maximum length of 125/16". In making the prefabricated blocks 36 either the depth of the recess 50 or the length of the extension 46 is maintained constant depending upon which measurement is more conveniently set up on the mold being used.

A joint according to the invention between adjacent blocks 36 and V36' is clearly illustrated in FIGURE 2. The extension 46 of the lower block 36 is received within the recess 50 of the upper blockV 36 so that the upper end of the extension of the lower block lining 38 engages the lower end of the lining `of the upper block. As shown in FIGURE 2, the annular space delined'between the upper end 60 of the body 4t) of the lower block 36 and the shoulder 56 at the lower end of the body of the upper. block 36' and between the outer surface 62 of the extension 46 of the lining 3S of the lower block and the axially extending surface 64 of the recess 50 is at least partially filled with `mortar 66 or similar cementious material.

When the chimney is erected, a small quantity of acid resistant cement is spread on the end of the refractory lining extension 46 of the lower in position block 36 and a small quantity of regular brick mortar is placed around the shoulder 60 of the same block. The next prefabricated section is installed by lowering it into position as concentrically and as plumb as possible on to the lower block 36. Recess 5t) of the upper block 36 will come down around extension 46 of the already in place lower block 36, as shown'in FIGURE 2, until the upper end of extensionr46 of the lower block engages the lower end of lining 38 of the upper block 36', thus bringing about an acid resistant joint between adjacent linings. As previously explained, the top and bottom of refractory linings 38 are not always parallel. This lack of parallelism is relatively slight and can easily be taken up with the acid resistant cement, so long as the cement is not first entirely squeezed out from between adjacent ends of the refractory lining sections. In other words, if the new blocks are settled into position, while in a near plumb concentric position, a perfect inner lining joint is achieved. The relatively heavy and wide mortar joint 66 between the upper end 60 of the body 40 ofthe lower block 36 and the shoulder 56 at the lower end of the body of the upper block 36' makes this easily possible. Even when the body 40 is of minimum thickness, the jointing area is relatively large, which, in conjunction with rather stiff mortar 66 gives the desired stability even though both jointing materials are in the green state. As can be readily seen, the design of the joint makes it very easy to separate and speedily apply both the acid-proof cement and the mortar with no danger of contaminating one with the other. Additionally evident is the fact that, even when one unit is being placed on, and settled down into position, there is no opportunity for joint material interference or contamination. The two joint materials do not normally contact one another in actual practice.

Any out of roundness, out of squareness, or actual differences in diameter of the refractory linings 38 is rendered inconsequential by the fact' that the diameter of the recess 50 is considerably larger than the outer diameter of the lining extension 46 of the adjacent block. The recess 50 not only provides additional space to compensate for the dimensional instability of refractory linings but also provides a limited area into which some of the jointing mortar can squeeze to further strengthen the joint.

It is to be understood that the prefabricated blocks 36 can, of course, be round, square, rectangular, or any other conventional shape. Also, the refractory lining 38 can be of one shape and the body of the thermal insulating material 40 of yet another cross-sectional shape. The thickness of the body of thermal insulating material 4t) can also be varied depending upon how much insulation is desired. For example, one thickness would be provided when the blocks are to be used in making a vent and a greater thickness used to make a chimney.

FIGURE 5 illustrates a modified form of a prefabricated chimney section, designated generally 68. This block differs from block 36 in that it has both inner and outer linings 38 and 70 of refractory clay or shale with an appropriate thickness of thermal insulating material 40 in between. This type of block has two dimensionally unstable components. The average difference in length between the inner lining 38 and the outer lining 70 must in this case be increased by the plus and minus variation of the outer lining. Variation in joint thickness is therefore considerably increased over that experienced when only the inner lining is dimensionally unstable.

FIGURE 6 illustrates a prefabricated block provided with a hollow laterally extending refractory lining 72 that engages the outer surface of the refractory lining 38 peripherally of an opening 74 formed through the refractory lining. The laterally extending refractory 1ining 72 may be secured to the outer portion of the refractory lining 38 by employing acid resistant cement between the inner end of lining 72 and the peripheral area 76 Iof the lining 38. The lining 72 is preferably secured to the lining 38 prior to casting of the body of insulating material 40 about the lining assembly. The T-shaped passageway in the block just described is used to provide means for connecting a fiue conduit 26 or 28 to the chimney as shown in FIGURE l.

The bottom block 30 of FIGURE l is shown in more detail in FIGURE 7 and is identical to the block shown in FIGURE 6 except that a cast iron hinged door assembly 32 is bonded to the peripheral area 7S of the lining 72 with acid proof cement. In addition the bottom surface 80' of block 30 is bonded to the floor 26 with acid proof cement.

Various other modifications and changes are contemplated and may obviously be restored to, without departing from the spirit or scope of the invention as hereinafter defined by the appended claims.

What is claimed is:

1. A prefabricated chimney comprising a plurality of block members superimposed on one another wherein each block comprises a body of thermal insulating material and a refractory lining having a passage longitudinally therethrough about which the body is molded, said refractory lining being of greater length than said body of thermal insulating material, the minimum difference in Athe length between the liningand the body of a block being the minimum desired mortar joint thickness between adjacent block members, said lining positioned so that it projects from and bey-ond one end of said body thereby defining a first shoulder extending radially outwardly from the refractory lining to the outer surface of the body, and means defining a longitudinally extending recess at the other end of said body, said lining terminating within said recess and defining a square shoulder with said body within said recess, said recess having a substantially greater width than said refractory lining, and a second shoulder at said other end extending between the louter extent of said recess and the outer surface of the body, the projection of said lining beyond said one end of the body is received within the recess of an adjacent block and engages the square shoulder defined within the recess of said adjacent block, the spaces defined between the rst and second shoulder of adjacent blocks being filled with mortar and a relatively thin layer of acid resistant cement being included between the engaging surfaces of the projection of said lining beyond said one end of the body and the square shoulder defined within the recess of said adjacent block and being separated from said mortar by the recess, the mortar and cement thereby bonding the blocks to one another.

2. A prefabricated chimney as set forth in claim 1 wherein the first and second shoulders define a horizontal surface.

3. A prefabricated chimney as set forth in claim 1 additionally including a layer of refractory material engagingly surrounding the body of each block.

4. A prefabricated chimney as set forth in claim 1 wherein at least one of the blocks includes means defining a laterally extending opening into the longitudinal passage of the refractory lining communicating with the exterior of said block.

5. A prefabricated chimney as set forth in claim 1 wherein the refractory lining comprises a material selected from the group consisting of burned clay and shale and mixtures thereof.

6. A prefabricated chimney as set forth in claim 1 wherein the body of the thermal insulating material cornprises a cementious material.

7. A prefabricated chimney as set forth in claim 1 wherein the minimum mortar joint thickness is onequarter inch.

S. A prefabricated chimney as set forth in claim l wherein the refractory lining and body of insulating material are coaxial.

9. A joint for a prefabricated chimney which includes a first block and a second block each having a hollow refractory lining and a body of insulating material coaxially engagingly surrounding said lining comprising: means defining an extension of said lining beyond the outer extent of one end of the body of the first block; means defining a recess in one end of the other of said blocks adapted to receive said lining extension, said lining extension of said first block engaging the lining of said second block within said recess, the width of said recess being substantially greater than the width of said lining, and the depth of said recess being shorter than said lining extension thereby defining a space between the body portions of said first and second blocks; the

space being filled with mortar, and a relatively thin layer of acid resistant cement included between the engaging surfaces of the lining extension of -the rst block and the lining of the second block and separated from said mortar by the recess, said mortar and cement serving to join the blocks to one another.

10. A joint as set forth in claim 9 additionally including a layer of refractory material engagingly surrounding the body of each block.

11. A joint as set forth in claim 9 wherein the lining Iof the first block extends from one to four inches beyond the outer extent of one end of the body of the rst block.

n i9 References Cited by the Examiner UNITED STATES PATENTS 843,797 2/1907 Dauben et al. 52-267 2,077,722 4/1937 Spring 52--267 2,128,463 8/1938 Kaurnann 52-218 FOREIGN PATENTS 78,884 2/1955 Denmark.

800,255 8/ 1958 Great Britain.

REINALDO P. MACHADO, Primary Examiner.

KENNETH DOWNEY, Examiner. 

1. A PREFABRICATED CHIMNEY COMPRISING A PLURALITY OF BLOCK MEMBERS SUPERIMPOSED ON ONE ANOTHER WHEREIN EACH BLOCK COMPRISES A BODY OF THERMAL INSULATING MATERIAL AND A REFRACTORY LINING HAVING A PASSAGE LONGITUDINALLY THERETHROUGH ABOUT WHICH THE BODY IS MOLDED, SAID REFRACTORY LINING BEING OF GREATER LENGTH THAN SAID BODY OF THERMAL INSULATING MATERIAL, THE MINIMUM DIFFERENCE IN THE LENGTH BETWEEN THE LINING AND THE BODY OF A BLOCK BEING THE MINIMUM DESIRED MORTAR JOINT THICKNESS BETWEEN ADJACENT BLOCK MEMBERS, SAID LINING POSITIONED SO THAT IT PROJECTS FROM AND BEYOND ONE END OF SAID BODY THEREBY DEFINING A FIRST SHOULDER EXTENDING RADIALLY OUTWARDLY FROM THE REFRACTORY LINING TO THE OUTER SURFACE OF THE BODY, AND MEANS DEFINING A LONGITUDINALLY EXTENDING RECESS AT THE OTHER END OF SAID BODY, SAID LINING TERMINATING WITHIN SAID RECESS AND DEFINING A SQUARE SHOULDER WITH SAID BODY WITHIN SAID RECESS, SAID RECESS HAVING A SUBSTANTIALLY GREATER WIDTH THAN SAID REFARACTORY LINING, AND A SECOND SHOULDER AT SAID OTHER END EXTENDING BETWEEN THE OUTER EXTENT OF SAID RECESS AND THE OUTER SURFACE OF THE BODY, THE PROJECTION OF SAID LINING BEYOND SAID ONE END OF THE BODY IS RECEIVED WITHIN THE RECESS OF AN ADJACENT BLOCK AND ENGAGES THE SQUARE SHOULDER DEFINED WITHIN THE RECESS OF SAID ADJACENT BLOCK, THE SPACES DEFINED BETWEEN THE FIRST AND SECOND SHOULDER OF ADJACENT BLOCKS BEING FILLED WITH MORTAR AND A RELATIVELY THIN LAYER OF ACID RESISTANT CEMENT BEING INCLUDED BETWEEN THE ENGAGING SURFACES OF THE PROJECTION OF SAID LINING BEYOND SAID ONE END OF THE BODY AND THE SQUARE SHOULDER DEFINED WITHIN THE RECESS OF SAID ADJACENT BLOCK AND BEING SEPARATED FROM SAID MORTAR BY THE RECESS, THE MORTAR AND CEMENT THEREBY BONDING THE BLOCKS TO ONE ANOTHER. 